HP12C - SST in RUN-Mode doesn't work correctly


A week ago I bought a new HP12C. Everything is working fine except SST-function in RUN-Mode. When the SST-button is holded down the program line should be shown, and on release of the button this line should be excecuted. But when I press down the button the line is not shown and the instruction is excecuted even before releasing the button.

Does anybody had this problem before? Can I resolve this problem by my own or do have to send the calculator for repair?

Thanks in advance for Your help.



I think Katie Wasserman reported this problem before. It is a bug in the new ARM-based 12c+. I believe Cyrille fixed it with a new version of the firmware, but you would need a special cable for your PC in order to install it. I'd call HP support and see if they can maybe send you a new unit.


Thanks a lot. I will contact HP. Let's see if they've a good customer support in the handheld, calculator devision.



It is indeed fixed in a later release along with a few related bugs and the self tests are now working like they should be (for the most part). I don't know if this release has yet made it into production, but you can check the version date by holding down [ENTER} + [g] when you turn on the calculator. Then press [2] followed by any other key and you'll see the version date. The last release that I have is 2009-11-19, but there might be something newer than that. See
this thread for a discussion of the SST bug, it was fixed in a version dated 2009-07-24.



Thanks a lot as well.

I'm new to HP Calculators and this forum and I'm surprised how helpful you are (and how deep you are all in this topic).

I really like the 12C a lot from the first minutes I used it. I hope I can solve the bug-problem fast.

By the way I read something about a 15C. Is this model in development? I really would buy one imediately!



'The' HP-15C was released in about 1981, and produced until about 1989. They command a premium on the primary internet auction site, and there are rumors that HP is going to release an updated version of this model.


Thank's Dan, for the information. As soon as they release the new version of the 15C I will buy one. The 12C has such a nice form factor, quality keyboard and simple, ergonomic user interface.

Have a nice day



The 12C has such a nice form factor, quality keyboard and simple, ergonomic user interface.

Unfortunately, it has the "landscape" keyboard layout which has proved to be less than optimal for a **handheld** calculator. I've used the HP-15C and HP-12C both for 24 years. The layout is cute, but it definitely "bites the big one" for real, actual, practical use as a **handheld**, regardless of two-handed or one-handed keyboard use.

Doubtless, HP learned from the Voyager landscape experiment that keyboards in that configuration should not be utilized on later machines (other than the never ending legacy of HP-12C mutants).

I doubt that HP will make the mistake of bringing back the HP-15C. Such a model would likely use the original HP-15C ROM image, which would be a tremendous step backward from its 1988 replacement, the excellent HP 42S. That is still the finest RPN calculator ever made (by very large margin over the HP-15C), now more than 22 years later.


I too like the 42S more than the 15C, but I don't think it would be a mistake to bring back the 15c with the original firmware but with a much, much faster processor. There are a lot of people here and elsewhere that would love to buy one or two 15C+ calculators. It would cost HP very little to manufacture given the 12C+ and would almost certainly sell 100K+ units easily (bring back the 15c). There's a good bit of money in this.


I keep hearing this arguement as to which was best; the 15c or 42s. They are very different machines and should not be compared. The 15c was simple to use with all its capabilities accessible directly from the keyboard without the need to run through endless menus and had a large clear numeric display. The 42s is a small computer with almost limitless capabilities, but as a daily user it is cumbersome just like the 28s, 48S and 50g. As far as which is best as a hand-held calc, I'd say neither; Woodstocks rule in this regard.


I've got a 50g but I don't use it every day. So it is a bit more difficult in use with the endless capabilities and menus and flags etc. The 15C would be the perfect machine for me. All the functions it has are just written on the keyboard which is for me also part of the UI. So there is no need in running and search in menus or even looking in the manual. It has enough functions and capabilities and is simple enough as a daily driver. I might buy two as well.

Have a nice day



Thank's a lot to everybody, especially to Cyrille who helped me out on this.

A nice day to everybody,


Possibly Related Threads…
Thread Author Replies Views Last Post
  Integration question and "RPN" mode comment Craig Thomas 16 5,847 12-05-2013, 02:32 AM
Last Post: Nick_S
  HP Prime: Recommendation for future RPN Program Mode BruceTTT 3 2,148 11-13-2013, 10:03 PM
Last Post: BruceTTT
  HP12c Present Value of $1.. Inaccurate??? Edward Dixon 12 3,639 11-12-2013, 11:32 AM
Last Post: Edward Dixon
  HP Prime: run a program in another program Davi Ribeiro de Oliveira 6 2,699 11-11-2013, 08:28 PM
Last Post: Davi Ribeiro de Oliveira
  emu48 - copy stack doesn't work (as expected) Thomas Radtke 2 1,963 11-11-2013, 02:19 PM
Last Post: Thomas Radtke
  HP PRIME: Hide return value from program and swap Edit with Run vrrr 2 1,541 11-09-2013, 04:04 PM
Last Post: vrrr
  Another Prime mystery - templates don't work anymore Michael de Estrada 2 1,343 11-02-2013, 11:34 AM
Last Post: Michael de Estrada
  Program to change entry mode on Prime Michael de Estrada 3 1,906 10-28-2013, 10:13 AM
Last Post: Han
  Prime: Exam mode (possible duplicate after funny response first time) Paul Townsend (UK) 1 1,483 10-24-2013, 03:09 PM
Last Post: Tim Wessman
  Does RPN entry mode cause the Prime keyboard to lock up ? Michael de Estrada 14 4,765 10-22-2013, 06:27 PM
Last Post: John Colvin

Forum Jump: